Goal of this fix is not to handle ASM_INPUT, rather the condition simplify.
Regards
Gang
On Sat, Dec 17, 2011 at 5:24 PM, Sun Chan <sun.c...@gmail.com> wrote:
> Also, I don't believe we ever designed WOPT to deal with ASM statements.
> To teach various phase to optimize asm stmt in wopt is not the goal.
> Sun
>
> On Sat, Dec 17, 2011 at 5:23 PM, Sun Chan <sun.c...@gmail.com> wrote:
>
>> if at O0, gcc optimized it, why is it the case different at O2?
>> Sun
>>
>> On Sat, Dec 17, 2011 at 5:18 PM, Gang Yu <yugang...@gmail.com> wrote:
>>
>>> For your questions:
>>> [1]. why the assertion,
>>> asm volatile ("%0" : : "i#*X"(x)); is a wrong assembler statement,
>>> it should be DCEed by optimizer and should not exist in CG phase.
>>>
>>> [2]. in order to get DCE. we should make condition
>>> _builtin_constant_p (x)
>>> && x != 0
>>> be folded to constant 0, intrinsic_op _builtin_constant_p(x) should be
>>> simplified to 0 and then let the optimizer further optimized
>>> _builtin_constant_p (x)
>>> && x != 0
>>> to 0
>>>
>>> [3]. at phase O0, _builtin_constant_p(x) is already folded to 0 by gcc.
>>> and the original case, with the __OPTIMIZE__ macro will not be enabled.
>>>
>>> Regards
>>> Gang
>>>
>>>
>>> On Sat, Dec 17, 2011 at 5:11 PM, Sun Chan <sun.c...@gmail.com> wrote:
>>>
>>>> Pls send more info for me to adequately review this fix.
>>>> Why do you suggest this fix. What is the problem with the assertion.
>>>> If you do that at -O0, what would happen?
>>>> Sun
>>>>
>>>> On Sat, Dec 17, 2011 at 12:52 AM, Gang Yu <yugang...@gmail.com> wrote:
>>>>
>>>>> Hi,
>>>>>
>>>>> Could a gatekeeper please help review the fix for bug595(
>>>>> https://bugs.open64.net/show_bug.cgi?id=595)?
>>>>>
>>>>> bug case:
>>>>>
>>>>> extern void doit(int);
>>>>> void
>>>>> quick_doit(int x)
>>>>> {
>>>>> if (__builtin_constant_p (x)
>>>>> && x != 0)
>>>>> asm volatile ("%0" : : "i#*X"(x));
>>>>> else
>>>>> doit(x);
>>>>> }
>>>>> Compiling quick_doit(0)
>>>>> "bug595.c", line 9: Error: Invalid 'asm' constrain : Cannot find
>>>>> immediate operand for ASM
>>>>> opencc ERROR:
>>>>> /fc/proj/ctires/open64/o64guru/OPEN64_X86_DBG/LATEST/bits//lib/gcc-lib/x86_64-open64-linux/5.0/be
>>>>> returned non-zero status 4
>>>>> Analysis:
>>>>> __builtin_constant_p(x) && x !=0 should be directly folded to if 0(it
>>>>> did not), then DCE does unreachable elimination, which finally sent out
>>>>> "doit" to CG.
>>>>>
>>>>> Suggested fix:
>>>>> index 148c4e2..42f55fb 100644
>>>>> --- a/osprey/be/opt/opt_htable.cxx
>>>>> +++ b/osprey/be/opt/opt_htable.cxx
>>>>> @@ -3575,7 +3575,9 @@ CODEMAP::Add_expr(WN *wn, OPT_STAB *opt_stab,
>>>>> STMTREP *stmt, CANON_CR *ccr,
>>>>> ccr->Set_tree(NULL);
>>>>> ccr->Set_scale(retv->Const_val());
>>>>> retv->DecUsecnt();
>>>>> - return FALSE;
>>>>> + // bug595 open64.net. intrinsic op folded to compile
>>>>> constant
>>>>> + // should be marked propogated for further
>>>>> fold/optimizations.
>>>>> + return TRUE;
>>>>> }
>>>>> if (retv->Kind() == CK_RCONST) {
>>>>> ccr->Set_tree(retv);
>>>>> Would a gatekeeper help the review? thanks
>>>>> Regards
>>>>> Gang
>>>>>
>>>>>
>>>>> ------------------------------------------------------------------------------
>>>>> Learn Windows Azure Live! Tuesday, Dec 13, 2011
>>>>> Microsoft is holding a special Learn Windows Azure training event for
>>>>> developers. It will provide a great way to learn Windows Azure and
>>>>> what it
>>>>> provides. You can attend the event by watching it streamed LIVE online.
>>>>> Learn more at http://p.sf.net/sfu/ms-windowsazure
>>>>> _______________________________________________
>>>>> Open64-devel mailing list
>>>>> Open64-devel@lists.sourceforge.net
>>>>> https://lists.sourceforge.net/lists/listinfo/open64-devel
>>>>>
>>>>>
>>>>
>>>
>>
>
------------------------------------------------------------------------------
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developers. It will provide a great way to learn Windows Azure and what it
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